Submersible pumping systems, such as electrical submersible pumps (ESP) are often used in hydrocarbon producing wells for pumping fluids from within the well bore to the surface. ESP systems may also be used in subsea applications for transferring fluids, for example, in horizontal conduits or vertical caissons arranged along the sea floor.
Pumps become less efficient when significant amounts of gas from the well fluid flow into the intakes. In a horizontal or highly deviated well, any gas in the well fluid tends to migrate to the upper side of the casing, forming a pocket of free gas. The gas tends to flow into a portion of the intake on the higher side of the pump intake.
Current solutions to this problem include gas restrictors, such as that described in U.S. Pat. No. 6,715,556, and gas separators, such as that described in U.S. Pat. No. 7,270,178. While the prior art types may be workable, they often have multiple moving parts which make them more complicated than necessary, increasing production costs and increasing the likelihood of mechanical failure. Another current prior art alternative would be to drill a sump with multilaterals but this method can add hundreds of thousands of dollars to drilling and production costs.